From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CDE1DC169C4 for ; Thu, 31 Jan 2019 12:08:07 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8FE04218AC for ; Thu, 31 Jan 2019 12:08:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="HGbUe8Q1" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8FE04218AC Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 2A6AE8E0002; Thu, 31 Jan 2019 07:08:07 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 256328E0001; Thu, 31 Jan 2019 07:08:07 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 145EF8E0002; Thu, 31 Jan 2019 07:08:07 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from mail-pl1-f197.google.com (mail-pl1-f197.google.com [209.85.214.197]) by kanga.kvack.org (Postfix) with ESMTP id C96168E0001 for ; Thu, 31 Jan 2019 07:08:06 -0500 (EST) Received: by mail-pl1-f197.google.com with SMTP id y2so2213011plr.8 for ; Thu, 31 Jan 2019 04:08:06 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:date:from:to:cc:subject :in-reply-to:message-id:references:user-agent:mime-version; bh=YS0NO5yiH+hzqGNX25wsvINs96sN7hTYyApoqyUzdY0=; b=Yr7MCpM6G8JBO2VxKBqMV0KIDoEq2kvhH2RrmGBr8d0QmfnMukANDidc0OsHfJQWX0 Bdyyntm62eImBrluKOyZ2ZcoryckxjsTz4AStoWdt1Q9RkCjK1GliVaRIltCELQe/EZ2 AdtfTHdL2+H6kcIMaT2751bmS2Fmlvp8EPDAo4UElfOhxzi6gS3E/iI/HDWXkqWwZt/4 YBK1c8i8igP/5T2kupfglqCGVgKONLIlri5p2+c9ChN9gYRCaFhylkeOYtYsC1RoMzJy q2NegWyUXiVBUZ8qAIWJGMhi18fEWVkSh/z1EvJf1IMdavr6sFGEMZ8L+cE1aTsjgssA F82g== X-Gm-Message-State: AJcUukcHbG9JUI9PBTJEuWka0weqkuJdnJVu2cO9W3TL14ji+83w07AK m2B01fXh56NpRVsbkM2CcnCTgFNc/5QnN0UQmxmAJRtxjINLmzm8Fb5E41hjeFRbCHm+MMxOs5G cjG0vZ6/t6wTEKmmVHvoELgSB4u5lTLSWgD13Mcd5DNlQCLvALGCLdsJWxJheAPzitQ== X-Received: by 2002:a17:902:7e44:: with SMTP id a4mr34596500pln.338.1548936486465; Thu, 31 Jan 2019 04:08:06 -0800 (PST) X-Google-Smtp-Source: ALg8bN7g4dBg4pcIXygkh5j61UNYap6vIS3SMrqBwPWYhfVpWY8xaD4TVqURSFUyuvpgZaoVraPE X-Received: by 2002:a17:902:7e44:: with SMTP id a4mr34596459pln.338.1548936485851; Thu, 31 Jan 2019 04:08:05 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1548936485; cv=none; d=google.com; s=arc-20160816; b=bc0oJEAcodmFCP7wGOJX2H9ZA9S8Y9izmFu2BbXxHMnyaamb/VgCWhirnOvlSpUEH4 F67RtpJfX+K1q/gKzA5Ty+S5GtBmmjTj1R1RvYQ9B6X+7kjEYx6dhgyOnT+twBqWru8/ oUVw7GnwG4ACPnspvdO0VAWvUW57q5+Od0x6S74/zHe38ZoDiKyP51isA/MZMKoz2JDq Kc9efYS7ruV4ppDvmGA6Ppk8BXLLWQv90CwalSGz5kh8B5RXJKw5DMs9thJybTtTrrSJ k/+G9uFdfzvw7ZhxZCLIOVCQE0SfkKVcJwBXD5goVRfrpWGrABoipJt2ecDX4qFWBDH7 LMhw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:message-id:in-reply-to:subject :cc:to:from:date:dkim-signature; bh=YS0NO5yiH+hzqGNX25wsvINs96sN7hTYyApoqyUzdY0=; b=BFeSVFP3AifzCDvDdkY2aQMXlbY3YjctWZcfgwzzBGHxl8AQiY5mvP7fpVIoAQsFhy 8wLJIP8PXqwEoruzVIDbDxK6kK01mU8jqHfNDGIr1WHNIUrOLPbxHCSUIuIbh4KmPZRP mu4vmw2JbjKbFJfWC0Nnw8pJJmNagXmyEpajZx9odN04yJsfTT9U/VaGRWYIkRPYGueg 7uCgXCzGcc8yUVEdCq0Anzs8qR61bI/C6O6UQOJpsGb2xfs8PccAa6PBiiTH8du4AE6R Qy+3yLYKO5pC4AafVPIGlAKyqKC9Fqkw5BUPji93aNNTOJmQB9SM9iZt5f5GIRWuwwwO k1PQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=HGbUe8Q1; spf=pass (google.com: domain of jikos@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=jikos@kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: from mail.kernel.org (mail.kernel.org. [198.145.29.99]) by mx.google.com with ESMTPS id 193si4058773pgc.220.2019.01.31.04.08.05 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 31 Jan 2019 04:08:05 -0800 (PST) Received-SPF: pass (google.com: domain of jikos@kernel.org designates 198.145.29.99 as permitted sender) client-ip=198.145.29.99; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=HGbUe8Q1; spf=pass (google.com: domain of jikos@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=jikos@kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: from pobox.suse.cz (prg-ext-pat.suse.com [213.151.95.130]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 823272086C; Thu, 31 Jan 2019 12:08:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548936485; bh=8xiqhQL74NPCiIrNIibRzSqNG12ZScZrkr4RT+/ftLI=; h=Date:From:To:cc:Subject:In-Reply-To:References:From; b=HGbUe8Q1y9wvs/YPD5E+gnIYoMx6uM84L7B+qKScVKjTy3XS9bKf3oqMNjO4lIWaJ mtmeCQSycFybNyNiIhRtBCY8yioMvLQ8WsXzv2sI+VsohOMh7wvEnIrEkcA7TZbDp8 5qkehS+eB/MhingrKgW+FQP5eleT04QyLDTmX4xg= Date: Thu, 31 Jan 2019 13:08:00 +0100 (CET) From: Jiri Kosina To: Daniel Gruss cc: Vlastimil Babka , Andrew Morton , Linus Torvalds , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-api@vger.kernel.org, Peter Zijlstra , Greg KH , Jann Horn , Dominique Martinet , Andy Lutomirski , Dave Chinner , Kevin Easton , Matthew Wilcox , Cyril Hrubis , Tejun Heo , "Kirill A . Shutemov" Subject: Re: [PATCH 2/3] mm/filemap: initiate readahead even if IOCB_NOWAIT is set for the I/O In-Reply-To: Message-ID: References: <20190130124420.1834-1-vbabka@suse.cz> <20190130124420.1834-3-vbabka@suse.cz> User-Agent: Alpine 2.21 (LSU 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, 31 Jan 2019, Daniel Gruss wrote: > If I understood it correctly, this patch just removes the advantages of > preadv2 over mmmap+access for the attacker. Which is the desired effect. We are not trying to solve the timing aspect, as I don't think there is a reasonable way to do it, is there? -- Jiri Kosina SUSE Labs